<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<style>
			.box {

				width: 300px;

				height: 300px;

				border: 1px solid red;

			}

			.box ul {
				height: inherit;
				display: flex;
				flex-direction: column;
				justify-content: center;
			}

			.box ul li {
				list-style: none;
				margin: 0 auto;
			}
		</style>
	</head>
	<body>
		<div class="box">
			<ul>
				　　<li>aa</li>
				　　<li>bb</li>
				　　<li>cc</li>
				　　<li>dd</li>
			</ul>
		</div>
	</body>
</html>
